Sawmill-dog.



H. M. LOFTON.

SAWMILL DOG.

APPLICATION FILED P11321, 1908.

`2 SHEETS-SHEET 1.

Patented Feb.16,'1909.

H. M. LOFTON.

SAWMILL DOG.

APPLIOATION FILED FEB. 1, 1908. Patented Feb. 16

2 SHEETS-SHBBT z.

lgf

UNITED sTATns PATENT ormoni.

HERBERT M. LOFTON, OF ATLANTA, GEORGIA.

SAWMILL-D OG.

Application filed February 1, 1908.

To all whom it may concern:

Be it known that l, HERBERT M. Lor'roN, a citizen of the United States,and a resident of Vthe city of Atlanta, county of Fulton, State ofGeorgia, have invented an Improvement in Sawmill-Dogs, of which thefollowing is a specifica-tion.

My invention has reference to sawmill dogs and consists of certainimprovements which are fully set forth in the following specificationand shown in the accompanying drawings, which form a part thereof.

The object of my invention is to provide ay sawmill dog' which shall beautomatic in the operations of its detail parts both of the upper andlower bits under the simple operation of a hand lever.

My object is also to provide a capacity to the dog such that it mayperform a triple function as more fully set out hereinafter.

My invention consists of a knee combined with a vertically movablerack-bar, a crosshead carrying an adjustable bit movable on therack-bar, a gripping bar on the cross head for clamping the bit and ahand lever' having' a sector engaging the rack-bar and operating tosimultaneously move the gripping bar and cross-head; also in the abovestructure combined with a. lower movable bit-head carrying a bit andadapted to clamp the bit in adjusted position by cam action of therack-bar upon the bit-head.

More generically, my invention consists of a vertically adjustable bar,combined with upper and lower bits, and hand operated devices forautomatically causing said bits to be moved toward each other to dog thetimber and also to be clamped to said bar.

My invention also comprehends details of construction which, togetherwith the features above specified, will be better understood byreference to the drawings, in which:-

Figure l is a front elevation of a sawmill dog embodying my invention;Fig'. 2 is aside elevation of the same; and Figs. 3, 4, 5 and G aresectional eleva tions of parts of the same on a larger scale.

The dog is attached to what is known as the knee which is arranged toslide in the head-block C, in the usual manner. The working parts of thedog are supported by the main upright bar B bolted to the knee C andhaving horizontal standards C2 and C3. The rack-bar A is arranged towork vertically in slots provided in the outer ends Specification ofLetters Patent.

Patented Feb. 16, 1909.

Serial No. l13,776.

of the standards C2 and C, as is shown in Figs. l and Q. A cross-head Ais arranged to slide on the rack-bar A vertically and is provided with aslot for supporting and guiding the bit AC which may be adjustedhorizontally. The upper end of the crosshead is provided with housingsA16 which have the vertical slotted holes All. A lever A2 is pivoted inthe housings and is provided with the toothed sector A3 which engage theteeth A7 of the rack-bar A. This lever' is also provided with the pinA4, which is intended to work freely in the slotted holes i 11. Thecross-head A is also provided at its lower end with housings forcarrying the gripping bar A, which is forked at its upper end to extendupon each side of the toothed sector A3. The lower end of this grippingbar has a wedge shape construction, the taper surface being on its outerside, as is indicated at A1".

The cross-head A opposite the bit AG is made with a socket for thegripping bar and is formed with an inclined 0r cam surface A forcooperating with the inclined surface A10 of the gripping bar A5, asclearly shown in Fig. l. The pin A4 is rigidly secured to the lever A2and aside from having its ends guided in the slots A11 of the housingsof the cross-head, it is also guided in slots A14 in the yoke portions r13 of the grip bar A5 to raise or depress it. The lower end of therack-bar A is provided with the bit-head D, which is provided with aslot through which the curved bit D'2 may slide freely for adjustmentwhen the dog is not in actual use. This bit-head is also provided with avertical slot Ds which permits the rack-bar A to have a limited verticalmotion relatively to the bit-head. It is also provided with the two camshoulders D', which engage cam portions DAL of the rack-bar A. Betweenthe cam portions DAL of the rack-bar is provided the straight parallelsurface D which engages the curved bit D2.

The operation may be described as follows z--The log, after it has beenrolled on the headblocks, is dogged, as shown in Fig. 2. The iirst partof the operation will be to raise the lever A2 to almost an uprightposition. This causes the toothed sector A3 to be revolved in therack-bar A until the teeth of this sector are entirely disengaged fromthe grooved teeth A7 therein. This permits the cross-head A and bit Asto be raised vertically on the rack-bar. This same movement of the leverA2 raises the gripping bar A5 by the action of the pin A1L before thecross-head A is raised. The raising of the gripping or wedge bar A5allows the bit A to be moved freely in the slot in the cross-head foradjustment. After raising the cross-head A to the proper height, the bitAG is moved out on a line where it is necessary to insert it in the log.The lever A2 is then pressed downward, which movement rengages thetoothed sector A3 in the teeth A7 of rack A, and the further depressionof the handle causes the cross-head A to move downwardly, inserting thebit in the timber. At the same time, the gripping bar A5 is caused to bepressed downwardly by a pin A4 of the lever A2, and by means of theinclined surface A9 said gripping bar is caused to clamp the bit A, thuspreventing the said bit from having any movement until it is againreleased by an upward movement of lever A2. As the lower bit D2 isintended to operate simultaneously with the upper bit AG, it isnecessary to describe the operation of this along with the operation ofthe upper bit.

It will be seen from the foregoing description that in clogging theupper bit, the raclxfbar A is moved upwardly, which causes it to slidethrough the bit-head D at the lower end. This sliding movement causesthe straight parallel surface D5 to be pressed against the lower bit D2by means of the cam action of the cam shoulders D* of the rack-bar Asliding against inclined or cam shoulders D of the slot D3 in the bithead D, thereby gripping the lower bit, and pulling it up into thetimber at the same time the upper dogging operation is carried on, ashas been previously described.

In order to undog or to release the bits from the timber, the followingoperation is necessary; The handle A2 is moved upwardly, raising thegripping bar A5, and thus taking the tension off of the bit AG. The nextwork performed by the upward movement of the lever, in addition to thatalready described, is to exert a downward push on the rack-bar A bymeans of the toothed sector A3. This downward pressure on rack-bar Acauses it to slide downward and release the lower bit D2. A furtherdownward movement of the rack-bar pushes the lower bit D2 out of thetimber, and at the same time carries the bitehead D along with it. Thisdownward move of the rackbar A continues until the pin A12 at its upperend is brought in contact with the standard C3. At this time the lowerbit D2 has been released so that it can slide horizontally through theslot in bit-head D. The lower bit has also been pressed down entirelyout of the timber, and the rack-bar A has been depressed as far down asit can go. A continuance of the upward movement of lever A2 serves toraise the cross-head A upwardly, thereby disengaging the bit A5 from theupper side of the timber; a still further upward movement of said leverA2 causes the toothed sector to be disengaged from rack A whereby thecross-head A may be raised vertically until it is entirely out of theway. After the cross-head has been raised, the lever A2 is again loweredand its sector A3 engages the rack A, as indicated in Fig. l, and inwhich position it is suspended until ready to dog in another piece oftimber.

The elliptic or curved form of lower bit D2 is important for thefollowing reasons: lf the lower bit D2 was straight, as is the case withthe upper bit A6, it would be seen that it would not dog a large roundlog on the bottom, as is shown in Fig. 2. By employing the curved formof bit, however, vthe outward movement will cause the point of the bitto be raised, so that it will engage the lower side of a large roundlog, and yet by being pressed backwards, it is quickly adjusted forengaging a square log. It is advisable that both of these bits A6 and D2in actual operation should be so arranged that they will not projectmore than onehalf inch from the end of the knee when they are adjustedback as far as they will go. The object of this is to allow the piece oftimber to be held by the dogs until there is only one inch remaining onthe saw carriage. This it will be seen allows one-half inch clearancebetween the outer edge of the bit and cutting edge of the saw. The aboveadvantages of the curved lower bit are quite important, especially inview of the fact that the vertical movement of the lower bit-head D isof necessity very limited. This is not so with the upper bit, as therange of vertical movement in this case is only limited by the length ofthe rack-bar A, and therefore it will be seen that the bit A6 having thestraight horizontal shank fulfills all require ments for the upper bit.

The dog has the following capacity: First; it will dog a square timberat the top with the upper bit pressed as far back as it will go; second,it will dog a square timber from the bottom with the lower bit pressedas far back as it will go; third, it will dog round log from the bottomby simply pushing the curved bit out until it comes in contact with thelog; thus giving to the dog a triple function. It is understood inconnection with this that the upper bit of course can be pushed out` anddog a round log from the top also as shown in Fig. 2, but this is trueof any ordinary dog; consequently, it is not considered that thiscapacity adds any additional function to the dog. The dog may thereforebe designated as a triplex dog.

By further references to Figs. l and 3, it

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will be noticed that the lever A2 is provided with the lug AS on itsunder side, which, when the lever is entirely dropped, will press on thegripping bar A5 and causing the gripping bar to press inwardly and gripthe bit A6. The object of this is that when the cross-head A is moved upentirely out of the way, and dog is not in use, this process justdescribed will hold the bit temporarily to keep it from working out infront of the saw, while the log is being sawed without being doggedIVhen the lower bit D2 is not in use, the weight of the bit-head D willdrop down on the rack-bar A, and by coming in contact with the camsurfaces D', it will grip this bit D2 at point indicated at D4, thuspreventing it from working out in front of the saw when this lower bitis not in use. Both of these features for locking the bits A and D2 areof the utmost importance in actual sawmill operations. It will be seenthat all these functions are entirely automatic, and each of them takescare of its own particular functions without any attention from theoperator, other than handling of the lever A2, and moving the bits in orout as may be required.

I have described my invention in the form which I have found excellentlyadapted for commercial use, and while I prefer the same, I do not limitmyself to the details thereof as these may be modified without departingfrom the spirit of the invention.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a sawmill dog, the combination ofthe head-block, an upright frameguided in the head-block, a rack-bar supported by the upright frame andvertically adjustable thereon, a cross-head carried by the rack-bar, alever having a toothed sector journaled in the cross-head with capacityof vertical movement thereon and engaging the rackbar, a bit carried byand adjustable transversely of the cross-head, and a gripping bar movedby the lever and arranged to clamp the bit in position.

2. In a sawmill dog, the combination of the head-block, an upright frameguided in the head-block, a rack-bar supported by the upright frame andvertically adjustable thereon, a cross-head carried by the rack-bar, alever having a toothed sector journaled in the cross-head with capacityof vertical movement thereon and engaging the rackbar, a bit carried byand adjustable transversely of the cross-head, and a gripping barcarried by the cross-head and adjustable vertically thereon whereby itmay be moved by the lever and arranged to clamp the bit in position.

3. In a sawmill dog, the combination of the head-block, an upright frameguided in the head-block, a rack-bar supported by the upright frame andvertically adjustable thereon, a cross-head carried by the rack-bar, alever having a toothed sector journaled in the cross-head with capacityof vertical movement thereon and engaging the rackbar, a bit carried byand adjustable transversely of the cross-head, a gripping bar moved bythe lever and arranged to clamp the bit in position, a bit-headadjustably secured upon the lower end of the rack-bar by means of camshaped parts, and a bit carried by the bit-head and arranged to beclamped between the bit-head and rack-bar when the upward .movement ofthe rack-bar is resisted by the clogging of the bit with the log.

4. ln a sawmill dog, a bit, a bit-head through which the bit extendslaterally, a vertically adjustable bar engaging and supporting thebit-head through cam connections so shaped that when the bar is raisedthe bit is clamped between the bar and bithead during the cloggingoperation of the bit.

5. In a sawmill dog, a vertically adjustable bar having a cam surface atits lower end, and means to suspend and raise the bar, combined with abit-head fitted upon the lower end of the bar and cooperating with itscam surface to clamp the bit, and a bit transversely adjustable upon thebit-head and adapted to be clamped upon the bithead while the log isbeing dogged by the bit and the bar raised.

(i. In a sawmill dog, a suspended bar arranged to be moved vertically, abit transversely adjustable with respect to the lower end of the bar,means for raising the bar during the act of clogging a log with the bit,and means carried by the bar for automatically clamping the bit to thebar during the upward movement of the bit and bar and when the upwardmovement of the bit is resisted by the log.

7. In a sawmill dog, the combination of a vertically adjustable barhaving cam surfaces D* and straight part D"I between them, with thebit-head D having a vertical slot D having cam surfaces D with which thccam surfaces D" of the bar engage, and a bit D2 extending through a slotin the bithead and arranged between the latter and part D of the bar.

8. In a sawmill dog, a suspended bar arranged to be moved vertically, abit transversely adjustable with respect to the lower end of the bar, asecond bit transversely adjustable with respect to the upper end of thebar, means for raising the bar during the act of clogging a log with thebit and automatically clamping the upper bit to the bar. and meanscarried by the bar for automatically clamping the lower bit to the barduring the upward movement of the said bit and bar and when the upwardmovement of the bit is resisted by the log.

9. In a sawmill dog, a vertically adjustable bar having' a cam surfaceat its lower end, and means to suspend and raise the bar, combined witha bit-head litted upon the lower end of the bar and cooperating with itscam surface to clamp the bit, a bit transversely adjustable upon thebit-head and adapted to be clamped upon the bit-head while the log isbeing dogged by the bit and the bar raised, a cross-head having asliding connection with the upper part of the vertically adjustable bar,an upper bit, and means on the cross head to clamp the bit to thecross-head automatically when the bar is being raised, whereby both theupper and lower bits ar-e dogged at one operation.

l0. In a sawmill dog, the combination of the bit head having a lateralcurved slot and a vertical slot openingl into the lateral curved slotand also provided above and below it with cam portions D3 and D4, acurved bit D2 fitting the lateral curved slot and guided by it, and avertical bar eX- tending through the vertical slot and having camportions co-acting with the cam portions of the slot and arranged toclamp the curved bit automatically when lifting it against a log inclogging the bit.

l1. The combination of the rack-bar A, the cross-head A movingvertically on same, a bit A6 extending transversely through thecross-head, the toothed sector carrying pin A4 loosely journaled in thecross-head so as to have vertical movement thereon and having a leverA2, and the gripping bar A5 adapted to be pressed downward by the pin ALof the toothed sector and its lever A2 and having at its lower end aparallel surface on one side for pressing against bit AG and on theother side having taper surface A9 for wedging the bit when the saidgripping bar is pressed downward, whereby the upward or downwardmovement of the lever A2 will cause this gripping bar to move in advancein either direction of the cross-head A.

l2. In a sawmill dog, the combination of the rack-bar, a cross-headadjustably supported thereon and having vertical slots, a bit carried bythe cross-head and adjustable transversely, a gripping bar having asliding cam connection with the cross head for causing it to grip thebit and clamp it in adjusted position and having a horizontal slot, atransverse pin extending through the vertical slots of the cross-headand hori- Zontal slot of the gripping bar, a sector secured to thetransverse pin and engaging the rack-bar, and a lever to rocl thesector.

13. In a sawmill dog, the combination of the rack-bar, a cross-headadjustably supported thereon and having vertical slots, a-

bit carried by the cross-head and adjustable transversely, a grippingbar having a sliding cam connection with the cross head for causing itto grip the bit and clamp it in adjusted position and having ahorizontal slot, a transverse pin extending through the vertical slotsof the cross-head and horizontal slot of the gripping bar, a sectorsecured to the transverse pin and engaging the rackbar, and a lever torock the sector having a clamping lug to press upon the gripping bar toclamp the bit when the same is not in use.

14. In a sawmill dog, the combination of a vertical bar, a cross-head, abit carried by the cross-head independently of the vertical bar andadjustable thereon, a gripping bar to clamp the bit carried with thecross-head to the cross-head alone, a pivoted lever device for adjustingthe cross-head upon the vertical bar and also arranged to press upon thegripping bar transversely to its direction of travel to cause it toclamp the bit when not in use.

l5. In a sawmill dog, the combination of a vertical bar provided at itslower end with a bit, a cross-head guided upon the vertical bar, anLipper bit guided in and supported wholly by the cross-head, means toclamp the upper bit to the cross-head alone, and hand operated means forsuccessively operating the means to clamp the upper bit and for raisingthe vertical bar in the cross-head whereby the upper and lower bits areforcibly moved toward each other.

16. In a sawmill dog, the combination of a vertical bar provided at itslower end with bit-head, a lower bit adjustably clamped between thebit-head and vertical bar, means for suspending the vertical bar withcapacity for limited movement, a cross-head guided upon the verticalbar, an upper bit guided in and supported wholly by the crosshead, meansto clamp the upper bitto the cross-head alone, and hand operated meansfor successively operating the means to clamp the upper bitand forraising the vei'-,v

tical bar in the cross-head whereby the upper and lower bits areforcibly moved toward each other.

17. In a sawmill dog, the combination of a vertical bar, means forsuspending the bar, heavy bit-head carried upon the lower end of theVertical bar and adjustable thereon, and an adjustable bit carried bythe bithead and arranged to be clamped between the vertical barandbit-head by the weight of the bit head coacting with the verticalbar.

18. In a sawmill dog, the combination of a rack-bar, means forsuspending it, a lower bit carried by the rack-bar, a cross-headadjustable upon the rack-bar, an upper bit carried wholly by andadjustable upon the cross-head, a gripping device on the crosshead forclamping the upper bit to the cross-head alone, and a sector engagingthe rack-bar and having means engaging the gripping device and thecross-head for operating them in succession.

19. In a sawmill dog, the combination of a rack-bar, means forsuspending it, a lower bit carried by the rack-bar, a cross-headadjustable upon the rack-bar, an upper bit carried wholly by andadjustable upon the cross-head, a gripping device on the crosshead forclamping the upper bit to the cross-head alone, and a sector engagingthe rack-bar and having means engaging the gripping device and thecross-head for operatin them in succession said sector being providedwith a hand lever and means for pressing upon the gripping devicetransversely to the direction of its travel and under the weight of thelever to clamp the upper bit when out of use.

20. In a sawmill dog, an upper adjustable bit, and a lower adjustablebit, combined with movable means connectin them, and hand controlleddevices carried y the mov able means for simultaneously clamping anddrawing the two bits toward each other when clogging a timber.

2l. In a sawmill dog, the upper and lower adjustable bits, a verticallyadjustable connection between the two bits, and hand controlled meansfor shortening the length of the connections between the bits andsimultaneously clamping and unclamping the bits upon the verticallyadjustable connection respectively with the shortening or lengthening ofsaid connection.

In testimony of which invention, I have hereunto set my hand.

HERBERT M. LOFTON.

Witnesses:

E. A. Donn, T. T. SMITH, J r.

